Special Senses Flashcards
- conscious or subconscious awareness of changes in the external or internal environment.
Sensation
conscious awareness and interpretation of sensations and is primarily a function of the cerebral cortex (parietal bone)
Perception
T or F
Adaptation - decrease in sensation during a prolonged stimulus
Some receptors are all rapidly adapting,
Your body adapts to different temperatures like when sinking into a hot tub
FLASE
Adaptation - decrease in sensation during a prolonged stimulus
Some receptors are rapidly adapting, others are slow
Your body adapts to different temperatures like when sinking into a hot tub
Sensory receptors - can be classified into:(3 ITEM)
free nerve endings,
encapsulated nerve endings, and
separate sense
General senses of touch (3 items)
Special senses (5 items)
General senses of touch
- Temperature
- Pain
- Pressure
Special senses
- (Smell)
- (Taste)
- Sight
- Hearing
- Equilibrium
Receptors for the special senses are housed in complex sensory organs such as eyes and ears
Special senses
—- - study of the eye and its disorders
——— study of the ears, noes, throat and their disorders
Ophthalmology - study of the eye and its disorders
Otorhinolaryngology - study of the ears, noes, throat and their disorders
what percent of sensory receptor is in the eye
70% of all sensory receptors are in the eyes
T or F
Protection of the eye
Most of the eye is enclosed in a bony orbit
A cushion of fat surrounds most of the eye
True
T or F
Each eye has over a million nerve fibers
True
Membrane that lines the eyelids
non keratinised stratified squamous epithelium
Connects to the surface of the eye
Secretes mucus to lubricate the eye
Conjunctiva
Eyelids & Eyelashes function
Anteriorly, the eyes are protected by the mobile eyelids or palpebrae
The eyelashes protect the eye from foreign objects, perspirations, and sunlight
The —– plate, a connective tissue, gives form and support to the eyelids
The——glands secrete oil to lubricate the eyelid and eye, it also prevents the eyelids from sticking together
The tarsal plate, a connective tissue, gives form and support to the eyelids
The tarsal glands secrete oil to lubricate the eyelid and eye, it also prevents the eyelids from sticking together
The ciliary glands, modified apocrine sweat glands, are found in between eyelash hair follicles
They are also called as glands of moll
Ciliary Gland
The ciliary glands, modified apocrine sweat glands, are found in between eyelash hair follicles
They are also called as glands of moll
Ciliary Gland
Modified sebaceous glands that produce an oily secretion to lubricate the eye
Meibomian Glands
—- gland: produces lacrimal fluid, moistens and lubricates the eye
——canals: drains lacrimal fluid from eyes
Lacrimal gland: produces lacrimal fluid, moistens and lubricates the eye
Lacrimal canals: drains lacrimal fluid from eyes
Tears: composed of?
Tears: composed of diluted salt solution, antibodies, mucous, lysozyme (destroys bacteria)
provides passage of lacrimal fluid towards the nasal cavity and is emptied via the nasolacrimal duct
Lacrimal sac
Explain the flow of tears
Lacrimal gland → lacrimal ducts → ocular surface → lacrimal puncta → lacrimal canaliculi → lacrimal sac → nasolacrimal duct → inferior nasal meatus → nasopharynx
Muscles attach to the outer surface of the eye
Produces eye movements
Extrinsic Eye Muscles
Extrinsic Eye Muscles Consists of four rectus muscles namely: and Also consists of two oblique muscles namely:
Consists of four rectus muscles namely:
- Superior rectus muscle
- Inferior rectus muscle
- Lateral rectus muscle
- Medial rectus muscle
Also consists of two oblique muscles namely:
- Superior oblique muscle
- Inferior oblique muscle
The wall is composed of three tunics:
Fibrous tunic: outer layer
Choroid (Vascular layer): middle layer
Sensory tunic: inner layer
White dense connective tissue layer made up mostly of collagen fibers and fibroblasts
Seen anteriorly as the “white of the eye
Gives shape to the eyeball, makes it more rigid
Sclera
Central, transparent coat that covers the colored iris
Allows for light to pass through and repairs itself easily
The only human tissue that can be transplanted without fear of rejection
Cornea
(Vascular Layer)
Lines most of the internal surface of the sclera
Blood-rich nutritive tunic
Pigment prevents light from scattering;
contains melanocytes
Choroid Layer